Response surface methodology, multi-objective optimization of biogas, and methane yield of pretreated Arachis hypogea shells

This study investigated the biogas and methane yield optimization of Arachis hypogea shells with the pretreatment method and the influence of three process parameters using the Response Surface Methodology (RSM) model. Arachis hypogea shells of different particle sizes were combined with 20 mg/L Fe3O4 nanoparticles and digested anaerobically. The RSM model was developed using three input variables to optimize and predict biogas and methane yield. The result showed that particle size reduction and Fe3O4 nanoparticle additives significantly influence the biogas and methane yield. The optimum yields were 8.03 and 6.18 ml/gVSadded, with R² values of 0.9889 and 0.8736 for biogas and methane.